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OFETs with sub-500 nm channel length were generated by UV assisted NIL with a commercially available UV-curing resist. A hybrid fused silica NIL-mold with adhesively bonded joint was developed in order to avoid the use of cost-intensive monolithic quartz molds. The adhesive layer, which was a UV-curing polymer, provided excellent homogeneity, low thickness, high UV-transparency, and high chemical resistance against many cleaning processes. A vapor phase deposition unit for perfluorinated silanes as antisticking layer (ASL) was applied. The generated silane ASLs were dense monolayers with a perfect coverage, a low surface free energy and a high stability against impacts caused by typical cleaning procedures as well as by UV-NIL process itself. A novel UV-NIL concept was proposed based on the use of an opaque silicon chip bonded to a transparent glass support. This technique was called as non-transparent UV-assisted NIL (NT-UV-NIL). It allowed the use of relative easily achievable silicon molds with the condition that the substrate must be transparent with a certain thickness in order to keep an acceptable indirect exposure dose. NTUV- NIL was well applicable for OFETs channel patterning without modifying the existing NIL system, which was initially designed for the "through-mold" UV exposure. A self designed UV-curable resist without cross-linking agent was developed in order to improve the dissolubility of the UV resist after exposure and therefore to facilitate the lift-off process. This dissoluble UV curing resist was well compatible with the subsequent lift-off process without applying a sacrificial underlayer. Another process to define short channels was developed based on the thermal assisted NIL (T-NIL). The use of a 4-inch wafer-scale NIL mold established a large-area NIL setup with improved throughput and increased production efficiency. The channel length on the silicon master wafer was downscaled to 100 nm range using i-line lithography and silicon reactive etching (RIE). In order to generate patterns much smaller than the exposure light wavelength, the OFET's source and drain features were exposed separately after each other. The final gap between the source and drain in the photoresist was determined by the stepper positioning accuracy, the resist film thickness, the resist mechanical stability, the substrate surface planarity, and the slope of images projected to the photoresist. A polymer based working template was replicated from the master wafer in order to avoid possible damages of the high-valuable master wafer during the NIL process caused by high pressure at high temperature. This applied polymer mold obtained an initial bulk antisticking property with a low surface free energy that was comparable with that of silane coated silicon surfaces. This technique established a process that can produce OFETs matrices with sub-100 nm channel lengths in a rapid and reliable way.